feat(portal): wire Accounts/Treasury/Reporting/Compliance/Settlements/TransactionBuilder to live Chain-138 + SolaceScan

Extends the POC from #2 beyond the Dashboard so every portal page that
can benefit from on-chain signal now pulls from live backends while
preserving its existing UX. Pages without an on-chain analogue (the
IFRS/GAAP/IPSAS report rows, the dbis_core compliance alerts) stay on
sample data with an explicit 'mocked' note.

New shared primitives
---------------------
src/hooks/useLatestTransactions.ts   — polls SolaceScan /transactions every 15s
src/hooks/useAddressTransactions.ts  — per-address tx feed, 60s polling
src/components/portal/LiveTransactionsPanel.tsx  — reusable live-tx card
src/components/portal/LiveChainBanner.tsx        — slim status banner
src/components/portal/OnChainBalanceTag.tsx      — shared live/off-chain pill

Per-page wiring
---------------
AccountsPage          — on-chain pill + META balance + SolaceScan link on
                        each account row that carries a walletAddress;
                        overlay renders only on wallet rows (negative check).
SettlementsPage       — replaces the static 'Settlement Rate' tile with a
                        live Chain-138 block + tx-today tile; adds a
                        LiveTransactionsPanel above the CSD queue so the
                        page no longer renders identical output when RPC
                        is dead.
ReportingPage         — new On-Chain Reporting Snapshot row (Blockscout
                        /stats: block depth, total tx, total addrs,
                        utilisation, avg block time). Clear note that
                        the IFRS/GAAP/IPSAS rows come from dbis_core and
                        are still mocked.
TreasuryPage          — two new summary tiles: live Chain-138 gas +
                        aggregated on-chain custody (META) from sample
                        wallet addresses. Uses the same
                        useOnChainBalances hook as Accounts.
CompliancePage        — AML monitor strip with wallet selector; dedicated
                        'On-Chain Tx Feed' card shows IN/OUT per tracked
                        wallet via SolaceScan. dbis_core alerts still
                        mocked (no public deploy).
TransactionBuilder    — LiveChainBanner inserted above the composer so
                        users know chain health + gas + latency before
                        composing; transaction-builder-module made a
                        flex column so the banner doesn't cover the
                        canvas.

Assertions baked into every live widget
---------------------------------------
- RPC failure flips colour + text to 'degraded'/'—' (no silent freeze).
- Loading state is distinct from both live and degraded.
- Each overlay is only rendered where real data differs from sample data
  (walletAddress rows for balances, tracked custody for AML, etc.) so a
  page without live overlays is proof-of-scope, not proof-of-brokenness.

Verified locally
----------------
- tsc --noEmit: clean
- npm run build: clean (2066 modules, 565 ms)

Still intentionally mocked
--------------------------
- proxmox.ts — CF-Access protected; a BFF route is now open in
  orchestrator PR (see companion PR for /api/proxmox/*).
- dbisCore.ts — no public deployment exists yet.

src/Portal.tsx

@@ -8,6 +8,7 @@ import ReportingPage from './pages/ReportingPage';
 import CompliancePage from './pages/CompliancePage';
 import SettlementsPage from './pages/SettlementsPage';
 import PortalLayout from './components/portal/PortalLayout';
+import LiveChainBanner from './components/portal/LiveChainBanner';
 import App from './App';
 
 function ProtectedRoute({ children }: { children: React.ReactNode }) {
@@ -64,8 +65,11 @@ export default function Portal() {
         element={
           <ProtectedRoute>
             <PortalLayout>
-              <div className="transaction-builder-module">
-                <App />
+              <div className="transaction-builder-module" style={{ display: 'flex', flexDirection: 'column', height: '100%' }}>
+                <LiveChainBanner />
+                <div style={{ flex: 1, minHeight: 0 }}>
+                  <App />
+                </div>
               </div>
             </PortalLayout>
           </ProtectedRoute>